This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is part of a multi-center traveling subject reproducibility study of DTI. The data will be used to evaluate the reliability of a diffusion tensor imaging protocol that will be used as part of a PREDICT, which is a multi-center (multi-vendor) DT imaging study of Huntington's disease (HD). The DTI data will be used to evaluate reliability of scalar metrics as well as fiber tracking of the motor, oculomotor, and limbic circuits. The 5 subjects will be recruited at Iowa and sent with an oil phantom to a number of centers where they will be imaged using a protocol that includes T1, T2, and Diffusion weighted images (see attached PDF). The scans will occur on Friday, October 19th, from 2pm-8pm. The images collected at our site as well as the images from the other sites will be transferred to Iowa for evaluation.